Fix error report for size overflow from transmute
Fixes#115402
The span in the error reporting always points to the `dst`, this is an old issue, I may open another PR to fix it.
Make if let guard parsing consistent with normal guards
- Add tests that struct expressions are not allowed in `if let` and `while let` (no change, consistent with `if` and `while`)
- Allow struct expressions in `if let` guards (consistent with `if` guards).
r? `@cjgillot`
Closes#93817
cc #51114
Add support to return value in StableMIR interface and not crash due to compilation error
Invoking `StableMir::run()` on a crate that has any compilation error was crashing the entire process. Instead, return a `CompilerError` so the user knows compilation did not succeed. I believe ICE will also be converted to `CompilerError`.
I'm also adding a possibility for the callback to return a value. I think it will be handy for users (at least it was for my current task of implementing a tool to validate stable-mir). However, if people disagree, I can remove that.
coverage: Explicitly test the coverage maps produced by codegen/LLVM
Our existing coverage tests verify the output of end-to-end coverage reports, but we don't have any way to test the specific mapping information (code regions and their associated counters) that are emitted by `rustc_codegen_llvm` and LLVM. That makes it harder to to be confident in changes that would modify those mappings (whether deliberately or accidentally).
This PR addresses that by adding a new `coverage-map` test suite that does the following:
- Compiles test files to LLVM IR assembly (`.ll`)
- Feeds those IR files to a custom tool (`src/tools/coverage-dump`) that extracts and decodes coverage mappings, and prints them in a more human-readable format
- Checks the output of that tool against known-good snapshots
---
I recommend excluding the last commit while reviewing the main changes, because that last commit is just ~40 test files copied over from `tests/run-coverage`, plus their blessed coverage-map snapshots and a readme file. Those snapshots aren't really intended to be checked by hand; they're mostly there to increase the chances that an unintended change to coverage maps will be observable (even if it requires relatively specific circumstances to manifest).
Rollup of 5 pull requests
Successful merges:
- #115353 (Emit error instead of ICE when optimized MIR is missing)
- #115488 (Take `&mut Results` in `ResultsVisitor`)
- #115492 (Allow `large_assignments` for Box/Arc/Rc initialization)
- #115519 (Don't ICE on associated type projection without feature gate in new solver)
- #115534 (Expose more information with DefId in smir)
r? `@ghost`
`@rustbot` modify labels: rollup
Don't ICE on associated type projection without feature gate in new solver
Self-explanatory, we should avoid ICEs when the feature gate is not enabled. Continue to ICE when the feature gate *is* enabled, though.
Fixes#115500
Allow `large_assignments` for Box/Arc/Rc initialization
Does the `stop linting in box/arc initialization` task of #83518.
r? `@oli-obk` who is E-mentor.
The output of these tests is too complicated to comfortably verify by hand, but
we can still use them to observe changes to the underlying mappings produced by
codegen/LLVM.
If these tests fail due to non-coverage changes (e.g. in HIR-to-MIR lowering or
MIR optimizations), it should usually be OK to just `--bless` them, as long as
the `run-coverage` test suite still works.
We compile each test file to LLVM IR assembly, and then pass that IR to a
dedicated program that can decode LLVM coverage maps and print them in a more
human-readable format. We can then check that output against known-good
snapshots.
This test suite has some advantages over the existing `run-coverage` tests:
- We can test coverage instrumentation without needing to run target binaries.
- We can observe subtle improvements/regressions in the underlying coverage
mappings that don't make a visible difference to coverage reports.
Do not require associated types with Self: Sized to uphold bounds when confirming object candidate
RPITITs and associated types that have `Self: Sized` bounds are opted out of the `dyn Trait` well-formedness check that happens during confirmation. This ensures that we can actually *use* `dyn Trait`s that have associated types that, e.g., have GATs and RPITITs and other naughty things as long as those are opted-out of object safety via a `Self: Sized` bound.
Fixes#115464
This seems like a natural part of https://github.com/rust-lang/rust/pull/112319#issuecomment-1592574451, and I don't think needs re-litigation.
r? `@oli-obk`
When writing a type-driven search query in rustdoc, specifically one
with more than one query element, non-existent types become generic
parameters instead of auto-correcting (which is currently only done
for single-element queries) or giving no result. You can also force a
generic type parameter by writing `generic:T` (and can force it to not
use a generic type parameter with something like `struct:T` or whatever,
though if this happens it means the thing you're looking for doesn't
exist and will give you no results).
There is no syntax provided for specifying type constraints
for generic type parameters.
When you have a generic type parameter in a search query, it will only
match up with generic type parameters in the actual function, not
concrete types that match, not concrete types that implement a trait.
It also strictly matches based on when they're the same or different,
so `option<T>, option<U> -> option<U>` matches `Option::and`, but not
`Option::or`. Similarly, `option<T>, option<T> -> option<T>`` matches
`Option::or`, but not `Option::and`.
Since `filename_for_metadata()` and
`OutputFilenames::path(OutputType::Metadata)` had different logic for
the name of the metadata file, the `.d` file contained a file name
different from the actual name used. Share the logic to fix the
out-of-sync name.
Closes 68839.
